Review Article
“Malignant” Perivascular Epithelioid Cell Neoplasm: Risk Stratification and Treatment Strategies
Table 1
Proposed classification of PEComas (adapted from Folpe et al. [
7]).
| High risk features | Risk category |
| (1) Size >5 cm (2) Infiltrative growth pattern (3) High nuclear grade and cellularity (4) Mitotic Rate >1/50 HPF (5) Necrosis (6) Vascular invasion | “Benign” <2 high risk features and size < 5 cm | | “Uncertain malignant potential” Size ≥5 cm with no other high risk features OR nuclear pleomorphism/multinucleated giant cells only | | “Malignant” 2 or more high risk features |
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